I want to know apart from simulators what are other methods.
there is no particular type..i need it generally for all.
also please tell me what are the tools available for these and where can i find it.

Syntax checking should be part of your developer, other than that the only reliable method I know of is to have an expierenced Engineer review the code. Short of this all testing is either on a simulator or at commissioning.
May be a good project for an industrious and creative programmer.
1. In put the process sequence of operations.
2. Add BOM.
3. Read the logic.
4. Verify end results.
Sounds simple enough.
Would you need verbal or ASCII input for this and would you want the output UL and CE certified?

I want to know apart from simulators what are other methods.
there is no particular type..i need it generally for all.
also please tell me what are the tools available for these and where can i find it.

I have written a program that analyzes the PLC program. It makes sure all IO is used in the program, and generates tables of constants, operator settings, event/alarm/trip conditions, and documents the interface between the PLC and HMI. It saves me from having to update documentation if the program has to be changed, and saves me from generating these specifics in the first place.

I recommend creating a good convention and structure for the parts of the program you want to automate the documentation or test-plan generation for as the program you write to parse your program will only be as good as you are at following the convention you create.